From: Jakub Kicinski <kuba@kernel.org>
To: Nikolaos Gkarlis <nickgarlis@gmail.com>
Cc: netdev@vger.kernel.org
Subject: Re: [PATCH] rtnetlink: add missing netlink_ns_capable() check for peer netns
Date: Thu, 26 Mar 2026 20:36:46 -0700 [thread overview]
Message-ID: <20260326203646.2da52419@kernel.org> (raw)
In-Reply-To: <20260324080730.4051666-1-nickgarlis@gmail.com>
On Tue, 24 Mar 2026 09:07:30 +0100 Nikolaos Gkarlis wrote:
> rtnl_newlink() lacks a CAP_NET_ADMIN capability check on the peer
> network namespace when creating paired devices (veth, vxcan,
> netkit). This allows an unprivileged user with a user namespace
> to create interfaces in arbitrary network namespaces, including
> init_net.
>
> Add a netlink_ns_capable() check for CAP_NET_ADMIN in the peer
> namespace before allowing device creation to proceed.
>
> Fixes: 48327566769a ("rtnetlink: fix double call of rtnl_link_get_net_ifla()")
AI assistant here suggests this is not the valid Fixes tag,
which seems true on the surface. This commit was fixing
cleanup, IDK how it could break input validation?
> Reported-by: Nikolaos Gkarlis <nickgarlis@gmail.com>
Reported-by tags are only when the reporter is different than author
the Google's bounty program rules have been amended to make this
explicit, please let us know if other programs still mislead people
> Signed-off-by: Nikolaos Gkarlis <nickgarlis@gmail.com>
--
pw-bot: cr
next prev parent reply other threads:[~2026-03-27 3:36 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-03-24 8:07 [PATCH] rtnetlink: add missing netlink_ns_capable() check for peer netns Nikolaos Gkarlis
2026-03-27 3:36 ` Jakub Kicinski [this message]
2026-03-27 8:55 ` Nikolaos Gkarlis
2026-03-27 16:03 ` Kuniyuki Iwashima
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